Erebos (binaural recording)

The synthesizer system operates using 24-channel speakers. These speakers are arranged in a rectangle measuring 167 cm in width and 141 cm in length, with the units facing inward. Eight front speakers are placed adjacent to each other at a height of 60 cm from the floor while eight rear speakers are placed similarly at a height of 30 cm from the floor. The left speakers are the first to fourth speakers along the left of the rectangle. The first speaker is placed 42.5 cm above the floor at the top; the second speaker is placed 35 cm from the front and 36 cm above the floor; the third speaker is placed 70 cm from the front and 36 cm above the floor; the fourth speaker is placed 105 cm from the front and 30 cm above the floor. The fifth to eighth speakers on the right are arranged in the same way as the speakers on the left. The 2-input, 8-output mixer performs sound source movement for the 8-channel speakers. It controls the sound source movement by inputting the control signal output from a universal serial bus (USB) device. Three mixers are used to control the eight front speakers, eight rear speakers, and eight left and right speakers. The system's filters include whitening filters, digital delay, a multiple synthesizer, and state variable filters. Two whitening filters and two state variable filters are used, and these circuits differ, resulting in different timbres. A multiple synthesizer mainly comprises a Wien bridge oscillator, multiplier, biquad circuit, and voltage control circuit. It functions when connected to a computer synthesizer via a line selector and buffer. A computer synthesizer comprises a computer and a USB device connected via a USB interface. In this speaker system, the front and rear speakers are placed at different heights, while the left and right speakers are at positioned gently sloping heights; this arrangement offers a sound source localization perception superior to that of a conventional speaker system. The system's performance was recorded with a dummy head microphone installed at the center of gravity of the rectangle formed by the speakers. Please listen to this music using headphones and enjoy the three-dimensional sound.